Electromagnetic field

An electromagnetic field was a type of field that was generated by electric devices, such as a holoprojector. B1-series battle droids were able to pick up the fields, as one B1 showcased during the Onderonian Civil War. The droid picked up an electromagnetic field, which was being generated from an imagecaster, and another droid pointed out where it was coming from. This battle droid walked to investigate the bag, with his two fellow units backing away in cowardice, but a message from Onderon's former king, Ramsis Dendup, soon began to play, and Dendup urged the Onderonian people to fight back against the Confederacy of Independent Systems. The civilian did as he requested, and the three battle droids that discovered the field were quickly destroyed. Tensor fields where a type of electromagnetic field.

Electromagnetic fields were first mentioned in Star Wars canon in Tipping Points, the fifth episode of Star Wars: The Clone Wars: Season Five.